Ball-mill plate.



J. M. SHERRERD. BALL MILL PLATE. APPLICATION FILED JULY 22. 1909.

Patented Sept.27,1910.

' To all whom 'ii may Camera:

JOHN M. SHERRERD, OF EASTON, PENNSYLVANIA.

BALL-MILL PLATE.

Specification of Letters Patent. Patented Sept. 2 7, 1910. Application filed July 22, 1909. Serial No. 508,891.

Be it known that I, JOHN M. SHERRERD, a citizen of the United States, residing in Easton, in the county of Northampton and State of Pennsylvania, have invented certain new and useful Improvements in Ball Mill Plates, of which the following is a specification. 1

The, present improvement relates to ball mills and lining plates therefor, the object of the invention being to provide an improved late simple in construction and which may e so fastened to the shell that the distortion of the lining made up by these plates will be reduced to a minimum, so that the holding bolts for the plates will be relieved of a large part of the strain thereon due to the tendency of the plates to shift around the shell.

A further object of the invention is the provision of an improved ball mill shell and lining plate so constructed that the strain on the holding bolts is largely relieved.

In the drawings accompanyin and forming part of this specification, Figure 1 is a view of a part of the shell, partly in section, with some of the-plates in position; and Fig. 2 is a perspective view of one of the plates detached.

Similar characters of-reference indicate corresponding parts in the drawings.

In that class of machines employed in crushing and pulverizing hard materials, such as cement, clinker, gold ores etc., and known as ball mills, ball tube mills, comminuters and the like, the crushing and pulverizin device consists essentially of a cylindrical shell of metal, such as steel or iron, arranged for rotation around a central shaft or other point of support. The shell is provided with a lining, frequently in the form of steps or shelves from which drops the material which is being crushed and the balls or pebbles which do the crushing. The edge of one shelf or step usually overlaps the edge of the next adjacent shelf or step, and these shelves or steps are sometimes made to extend the full length of the cylinder and are frequently attached to the cylindrical wall of the shell itself by belts or rivets, these shelves or steps being made either in one or several pieces. When the shelves or steps are secured to the shell by bolts or rivets, which latter usually extend through the shell, especially when these shelves or steps are made of unmachineable metal such as manganese steel, which, owing to its tough ness and resistance to abrasive wear, is particularly well suited for this purpose, the shelves or steps tend to distort under the blows of the balls or crushing material and this tends to bring a somewhat greater strain on the bolts than is desirable, this being due in part to the ductility of the metal, which causes it to flow to a small extent and change shape, and thus, as stated, the shelves or steps tend to distort under the blows of the balls or crushing material, so that the bolts not only have to hold the plates against the shell, but also have to resist the tendency of the lining to shift around the inside circumference of the shell. The present improvement is therefore intended to reduce this distortion of the lining to a minimum and so take the strain off from the holding bolts, and for this purpose I have provided an improved construction of plate.

In the present embodiment of the invention the shell 2 is provided at intervals around the same, interiorly thereof, with a series of ribs or bars 3 riveted or otherwise secured on the inner wall of the shell. The ball mill or comminuter plate l, usually provided with a slotted end or heel 5 for the reception of bolts 6, is also provided with a lug or shoulder 7 integral with the plate and located in position to rest against one of the ribs or bars on the shell. The plate is also provided adjacent to its opposite or toe end with openings 8 for the holding bolts or rivets 6. The plates are assembled so that the toe of one overlaps the heel of a companion plate, whereby such juxtaposed ends may be secured to the shell by the same set of bolts. In this position the shoulder or lug of each plate rests against one of the ribs or bars of the shell, whereby the strain on the bolts which secure the lining plates tothe shell is greatly relieved by reason of the fact that any distortion of the plates under the blows of the balls or crushing material will be received by the ribs or bars of the shell instead of by the bolts, especially as the toe ends of the plates are curved outward and so formed between this integral shoulder and the bolts that distortion of the plates tends to more firmly cause the shoulder of each plate to engage its rib, this being due somewhat to the fact that the curved toe end of the plate is spaced from the rib in such a manner that pressure on the working face of the plate causes the shoulder to firmly engage its shell rib.

In this improvement the plates are chambered and ribbed for the purpose of strengthening the same at the toe end thereof between the shoulder hereinbefore referred to and the toe ends, the parallel strengthening ribs 10 being located in position to engage the heel of a companion plate.

In practice the bolt holes 8 could be made somewhat elongated if preferred, thereby to avoid strain being brought against the bolts when the plate is straightened out under the blows of the balls or pebbles.

It will be observed that the chambered and rib reinforced toe .of the plate is not only effective to strengthen the plate and thus prevent distortion of it by preventing its peening or straightening out in action, but these reinforcing ribs also act as spacing means to locate the plate in the properposition with relation to the shell so that it will form the proper step in connection with the heel of its companion plate.

In practice it is desirable that the plate shall have a curved working face from a point toward the heel to a point toward the toe, and in order to permit it to have a proper step formation with a companion plate it has heretofore been necessary to insert a filler between the heel of one and the toe of the other. This filler, however, being a separate piece, does not in any way reinforce the plate or prevent its distortion, Whereas in the present improvement, by forming the plate with a ribbed toe, thes'e ribs not only act to space the'plate from the heel of the companion plate and thus do away with an independent filler, but they also act to reinforce the curved plate in such a way as to prevent its peening or straightening out or distortion.

I claim as my invention:

1. A lining plate having a toe and heel and between said toe and heel a shoulder projecting from its non-working side.

2. A lining plate having a toe and heel and between said toe fiid heel a transversely extending shoulder projecting from its nonworking side and extending from side to side of the plate.

3. A lining plate having a slotted heel, a chambered and rib reinforced toe, and provided with a curved working face and having between its heel and toe a transversely extending shoulder projecting from its nonworking side.

4. A lining plate having a chambered and reinforced toe end and a slotted heel end, and between such ends a' transversely extending integral shoulder projecting from its non-working side.

5. In a ball mill, the combination of a shell having a transversely extending rib, and a lining plate bolted to said shell and having a shoulder projecting from its nonworking side for engaging said rib. v

6. In a ball mill, the combination of a shell having a series of transversely extending bars or ribs secured thereto, and a lining comprising a plurality of plates, the toe of one overlapping the heel of another, each pair of plates bolted through its heel and toe to said shell and each of said plates having a transversely extending shoulder projecting from its non-working side and in position to engage one of the bars of said shell.

7. In a ball mill, the combination of a shell having a series of transversely extending bars or ribs secured thereto, and a lining comprising a plurality of plates, the toe of one overlapping the heel of another, each pair of plates bolted through its heel and toe to said shell and each of said plates having a transversely extending shoulder proj ecting from its non-working side and in position to engage one of the .bars of said shell, each plate having a curved working face. I

8. In a ball mill, the combination of a shell having a series of transversely extending bars or ribs secured thereto, and a lining comprising a plurality of plates, the toe of one overlapping the heel of another, each pair of plates bolted through its heel and toe to said shell and each of said plates having a transversely extending shoulder proj ecting from its non-Working side and in position to engage one of the bars of said shell, each (plate having a curved Working face space from its bar of the shell.

9. In a ball mill, the combination of a shell having a series of transversely extending bars or ribs secured thereto, and a lining comprising a plurality of plates, the toe of one overlapping the heel of another, each pair of plates bolted through its heel and toe to said 'shell and each of said plates having a transversely extending shoulder projecting from its non-working side and in position to engage one of the bars of said shell, each plate having a curved working face spaced from its bar of the shell and also having a chambered and rib reinforced toe.

10. In a ball mill, the combination of a shell having a rib or bar secured to the in.- ner wall thereof, and a lining plate bolted to said shell and having a curved portion spaced from said bar and provided with a shoulder projecting from its non-working side and adapted to engage said bar thereby to resist the distortion of the lining and relieve the strain on the holding bolts.

11. A lining plate having a toe and heel and substantially midway between said heel and toe a transversely extending shoulder projecting from its non-working side.

a 12. A ball mill lining plate having a toe and heel and between said heel and toe a curved working face, the toe having a plurality of reinforcing ribs on its rear side.

13. A ball mill lining plate having a toe and heel and between sald heel and toe a curved Working face, the toe ortion having a plurality of reinforcing r1 s on its rear side, some extending transversely of others.

14. A ball mill lining plate havin and heel and between said heel an toe a curved working face, the toe having a plua toe rality of reinforcing ribs onits rear side, said plate also having on its-rear side between its heel and the ribs a transversely extending shoulder projecting from its nonworking side.

Signed at 9 to 15 Murray street, New York, this 19th day of July, 1909.

JOHN M. SHERRERD.

Witnesses:

C. A. WEED, T. E. BOYCE. 

